Shock wave drilling called shock tubes earth drill

ABSTRACT

This earth drill is a parallel array of combustion type shock tubes whose shock waves are directed into a hole for loosening and moving aside earth and rock and in which means are employed for simultaneous ignition of the combustible gases or vapor fuel and oxidizer mixture in each of the tubes, the various positionings of the tubes in the array relative to each other in different embodiments is such that the open end of each tube which directs the shock of that tube down into the hole may have a different elevation from any or all of the other tubes as to produce a desired interaction of the shock waves from the tubes in the array and thereby produce an aggregate shock wave either focused principally downward or one at any of several degrees of downward and outward. The geometry of the shock directing end of each shock tube may vary to enhance the directive effect.

United States Patent 91 OHare Sept. 25, 1973 SHOCK WAVE DRILLING CALLED SHOCK TUBES EARTH DRILL Louis Richard OHare, 2700 Indiana NE, Albuquerque, N. Mex. 87110 [22] Filed: Dec. 27, 1971 [21] Appl. No.: 192,712

[76] Inventor:

Primary ExaminerMarvin A. Champion Assistant ExaminerRichard E. Favreau 5 7 ABSTRACT This earth drill is a parallel array of combustion type shock tubes whose shock waves are directed into a hole for loosening and moving aside earth and rock and in which means are employed for simultaneous ignition of the combustible gases or vapor fuel and oxidizer mixture in each of the tubes, the various positionings of the tubes in the array relative to each other in different embodiments is such that the open end of each tube which directs the shock of that tube down into the hole may have a different elevation from any or all of the other tubes as to produce a desired interaction of the shock waves from the tubes in the array and thereby produce an aggregate shock wave either focused principally downward or one at any of several degrees of downward and outward. The geometry of the shock directing end of each shock tube may vary to enhance the directive effect.

4 Claims, 5 Drawing Figures PATENTED sum 1 or 2 Fig. 2

Fig. I

r 1 SHOCK WAVE DRILLING CALLED SHOCK TUBES EARTH DRILL SUMMARY OF INVENTION My invention employs the use of a shock tube of the combustion type to produce a hole in the earth. It especially involves a device which comprises an array of 7 these tubes to direct the explosive surge of pressure toward the area to be drilled after the manner of a shaped charge. Shock waves of mach 20 have been achieved from strong cylindrical steel tubes when properly designed fueled and ignited. There is a great deal of energy in a mach 20 shock wave when the wave is large enough and my inventive concept concerns the use of this energy for breaking, loosening and thrusting aside of the earth in order to produce a hole. The minimum dimensions required for a strong steel cylinder to produce a shock wave from a combustible mixture of gas or vapor fuel andoxidizer are about 1 inch in diameter and 3 feet in length. When such a tube or one larger is sealed securely on one end and closed with a breakable diaphragm on the other end and the mixture is ignited by an electric igniter at the securely sealed end, the resulting gas combustion. produces a pressure surge which ruptures the diaphragm at the other end producing a shock wave. At the center of the pressure disturbance temperatures can reach values of 20,000 K or more. There even occurs a great deal of electronic ionization. All of this constitutes a concentration of much energy in a small area. Such energy directed against earth and rock will break it and move it. Hence the use of a combustion generated shock wave as an'energy source for producing a hole is one embodiment of this invention. But another embodiment consists in aggregating together the shocks from many tubes to generate a highly directed shock wave for the benefit ofa greater concentration of energy and more effective drilling action. The relative placement of many shock tubes held parallel to each other within the confines of a large outer cylinder whose length is parallel to thelengths of the inner shock tube cylinders will produce a multiple shock tube drill bit when the exiting or diaphragm end of these tubes is directed at the earth to be drilled.

If in the process of constructing this bit the inner tubes were momentarily allowed to move freely in a lengthwise movement only and the exiting ends, facing downward were placed over a cone whose peak was upward and whose axis was directly in line with the axis of the large cylinder, then the shock tubes in the center of the large cylinder would be moved farther upward inside the large cylinder than those nearer the circumference. Those midway to the circumference of the large cylinder would occupy a mid position in elevation etc. Subsequently when all cylinders so positioned are made rigid relative to each other in this positioning and the cone is removed, the result inside the larger cylinder is a near conical cavity walled by shock tubes. The cavity may be further machined to be formed more conical still with the result that the shock tube exit ports will no longer be at right angles to the length of the shock tubes. The shock wave produced by such an aggregation would be to some extent directed along the axis of the large cylinder. The smaller the angle across thepeak of the cone the more concentrated the energy of the aggregate shock wave along the axis of the large cylinder. A conical cavity of moderate angle across its peak would produce a compromise shock wave front partially spherical in shapewhich would blow a hole both downward and outwaid preventing the bit from being bound in an earthen hole of inadequate diameter by moving earth or rock outward as wellas downward. In every case the distinguishing characteristic is the application of an authentic shock wave from the shock tube by the determination of appropriate dimensions of the tube rather than a mere random detonation of combustibles in a tube.

The second distinguishing note of this inventive concept is the configuration of the exit port to focus or form the wave front of this kind of a shock wave. Another distinguishing characteristic is the use of water seal at the bottom of the hole covering the exit ports but not filling the shock tubes which take the place and function of the breakable diaphragms in shock tubes used for other purposes.

FIG. 1 of the drawings is a shock tube earth drill in which a single shock tube is used as an earth drill with the earth and water against its drilling end acting to replace the diaphragm found on most shock tubes.

FIG. 2 is a cross sectional drawing of an array of shock tubes clustered at different elevations in a cylinder to form a conical cavity and cause a shaped charge effect at the drilling end. I

FIG. 3 is a three dimensional view of a sectional cut taken through the diameter of the array of shock tubes forming a cone at the exit end to direct shock wave force along the axis. I

FIG. 4 is an electric probe used to determine gas volume in the shock tube drill.

FIG. 5 is a cross sectional view of a shock tube array drill in which the exit angles of the individual shock tubes are cut at angles to better form a cone and direct the energy of the shock wave.

In FIG. 1 of the drawings number 1 is the shock tube. It must be at least one inch in diameter and 3 feet long to produce a minimum shock wave. This shock tube is connected to drill insertion pipe 2 which lowers the shock tube into the hole. Threading is used to make this connection. Fuel and oxidizer ports 3 and 4 bring combustion components into shock tube from fuel and oxidizer lines 5 and 6. Ignition and ground wires 7 and 8 bring electric current to electric igniter 9 which ignites the gas when the gas has filled the tube thereby producing a shock wave which is directed against the earth to be drilled.

In FIG. 2 of the drawings 10 is a collection of many tubes of the kind shown in FIG. 1. The large outer cylinder enclosing and supporting these tubes is shown by 11. The fuel, ignition, and oxidizer supply lines to the individual shock tubes are shown by numbers l2, l3, and 14 and these correspond to numbers 5, 7 and 6 respectively of FIG. 1. All of the individual tubes fuel lines connect to main fuel line. All of the separate individual ignition lines connect to the main drill ignition line 17. All of the individual shock tubes oxidizer lines connect to the main oxidizer line 16. The groundline for ignition is shown by 18 and the grounding current is carried to ground the shock tubes by the electrical contacting of the metallic surfaces of the tubes with the outer cylinder which is connected to 18. The steep conical cavity 19 forms the energy from the several shock waves into concentrated energy along the axis of the drill cylinder. The angle across the peak of this conical cavity determines the degree to which force is directed downward. With a wide angle much of the force would be directed outward as well as downward. When a great concentration of downward force is desired to penetrate harder rock a bit with a narrower angle across its conical cavity would be used. The sealed upper conical cavity 43 enables simultaneous ignition of shock tubes through small ignition ports 44 and conical cavity 43 is covered by sealed conical cover 45.

In FIG. 3 there is pictured at three dimensional view of a lengthwise cut made across the diameter to show 20, the ring of shock tubes around the circumference being of lower elevation than 21 the ring which is inside that outer ring. With a still more central ring of tubes 22 being higher yet, the tube on the axis of the cylinder 23 is highest of all. The number 24 is the outer enclosing steel cylinder which supports the array.

In FIG. 4 the probe 31 is electrically contacting the water at the bottom of shock tube 32 thereby closing the electric circuit and energizing solenoid which holds down pivot arm and keeps valve piston 35 in down position enabling valve ports 36 and 37 to allow gas flow through to fuel and oxidizer lines. Subsequently when gas forces water away from probe the circuit is broken pivot arm 34 moves up closing valve and stopping fuel supply.

In FIG. the number 40 is the shock tube array with exit ends machined to shape a steep conical cavity 42 and 41 is the outer cylinder. The steepness of cavity 42 may be altered in various embodiments by a change in positioning of shock tubes. When the tubes closer to the center are not as far upward the conical cavity does not form a steep cone with a small angle across its peak but it thereby has a larger angle across its peak to give more outward component to combustion force.

What I claim is:

1. A drill for producing deep holes in the earth comprising a combustion type shock tube composed of a strong steel tube or cylinder of at least the minimum dimensions required to produce a shock wave from combustible gas or vapor and oxidizer mixture when ignited by an electric spark such minimum dimensions being at least 1 inch in diameter and 3 feet in length said tube being positioned at any angle toward the earth that it is able to discharge from the exit end of the tube a shock wave into the earth to be drilled, the opposite or upward end of said tube being sealed and fitted with fuel and oxidizer ports and a means of ignition and having fuel and oxidizer lines fitted to these ports with electric high voltage and grounding cables having suitable igniter and grounding connections to which they are attached, the exit end of said shock tube being held by its own weight against the moistened earth to be drilled or in water or fluid immediately above the earth to be drilled to provide a stoppage for the pressure build up reaction whereby when electricity from a spark coil ignites the mixture a shock wave is produced ejecting very high speed hot gas imparting energy to break up and move aside earth and rock to produce a hole.

2. An earth drill comprising an array of several or more such shock tube drills as described in claim 1 said array consisting of a placement in an outer enclosing steel cylinder said shock tubes parallel to each other and to the enclosing larger cylinder along their lengths but with the exiting ends having various elevations from the earth against which their blast is directed resulting in that shock tube whose length is along the axis of the enclosing cylinder having its shock wave exit opening considerably higher from the earth and from the open end of the large enclosing cylinder than those shock tubes which are close to the circumference and resulting in those shock tubes whose position is intermediate between the axis and the circumference of the large cylinder having an elevation between the elevation of the tubes on the axis and those near the circumference thereby producing a steep conical cavity inside the large tube which produces the effect of a shaped charge in that the shock waves from the equilength shock tubes will reach the cavity at the same time producing a strong wave with force concentrated along the axis, with all of the simultaneous ignition required being provided by parallel electric circuitry to the electric igniters and by small ignition ports opening into a sealed steep conical cavity at the upper end of the shock tubes, this cavity resulting from a sealed conical cover on the upper end of the outer cylinder said conical cover having the point of its cone upward and being provided with ignition and fueling ports.

, 3. An earth drill as claimed in claim 2 in which the individual shock tube exit ports are machined and their geometry changed so that their circumferences are no longer at right angles to the length of the shock tube but are shaped to such angles as to form a cavity more nearly fully conical in shape.

4. An earth drill comprising an array of several or more such shock tube drills as described in claim 1 said array consisting of a placement in an outer enclosing steel cylinder said shock tubes parallel to each other and to the enclosing larger cylinder along their lengths but with the exiting ends having various elevations from the earth against which their blast is directed resulting in that shock tube whose length is along the axis of the enclosing cylinder having its shock wave exit opening considerably higher from the earth and from the open end of the large enclosing cylinder than those shock tubes which are close to the circumference and resulting in those shock tubes whose position is intermediate between the axis and the circumference of the large cylinder having an elevation between the elevation of the tubes on the axisand those near the circumference thereby producing a shallow conical cavity inside the large tube which produces the effect of a shaped charge in that the shock waves from the equilength shock tubes will reach the cavity at the same time producing a strong wave with force concentrated along the axis, as well as with some spherical component to impart energy both downward as well as outward for adequate hole diameter enlargement with all of the simultaneous ignition required being provided by parallel electric circuitry to the electric igniters and by small ignition ports opening into a sealed steep conical cavity at the upper end of the shock tubes, this cavity resulting from a sealed conical cover on the upper end of the outer cylinder said conical cover having the point of its cone upward and being provided with ignition and fueling ports. 

1. A drill for producing deep holes in the earth comprising a combustion type shock tube composed of a strong steel tube or cylinder of at least the minimum dimensions required to produce a shock wave from combustible gas or vapor and oxidizer mixture when ignited by an electric spark such minimum dimensions being at least 1 inch in diameter and 3 feet in length said tube being positioned at any angle toward the earth that it is able to discharge from the exit end of the tube a shock wave into the earth to be drilled, the opposite or upward end of said tube being sealed and fitted with fuel and oxidizer ports and a means of ignition and having fuel and oxidizer lines fitted to these ports with electric high voltage and grounding cables having suitable igniter and grounding connections to which they are attached, the exit end of said shock tube being held by its own weight against the moistened earth to be drilled or in water or fluid immediately above the earth to be drilled to provide a stoppage for the pressure build up reaction whereby when electricity from a spark coil ignites the mixture a shock wave is produced ejecting very high speed hot gas imparting energy to break up and move aside earth and rock to produce a hole.
 2. An earth drill comprising an array of several or more such shock tube drills as described in claim 1 said array consisting of a placement in an outer enclosing steel cylinder said shock tubes parallel to each other and to the enclosing larger cylinder along their lengths but with the exiting ends having various elevations from the earth against which their blast is directed resulting in that shock tube whose length is along the axis of the enclosing cylinder having its shock wave exit opening considerably higher from the earth and from the open end of the large enclosing cylinder than those shock tubes which are close to the circumference and resulting in those shock tubes whose Position is intermediate between the axis and the circumference of the large cylinder having an elevation between the elevation of the tubes on the axis and those near the circumference thereby producing a steep conical cavity inside the large tube which produces the effect of a shaped charge in that the shock waves from the equilength shock tubes will reach the cavity at the same time producing a strong wave with force concentrated along the axis, with all of the simultaneous ignition required being provided by parallel electric circuitry to the electric igniters and by small ignition ports opening into a sealed steep conical cavity at the upper end of the shock tubes, this cavity resulting from a sealed conical cover on the upper end of the outer cylinder said conical cover having the point of its cone upward and being provided with ignition and fueling ports.
 3. An earth drill as claimed in claim 2 in which the individual shock tube exit ports are machined and their geometry changed so that their circumferences are no longer at right angles to the length of the shock tube but are shaped to such angles as to form a cavity more nearly fully conical in shape.
 4. An earth drill comprising an array of several or more such shock tube drills as described in claim 1 said array consisting of a placement in an outer enclosing steel cylinder said shock tubes parallel to each other and to the enclosing larger cylinder along their lengths but with the exiting ends having various elevations from the earth against which their blast is directed resulting in that shock tube whose length is along the axis of the enclosing cylinder having its shock wave exit opening considerably higher from the earth and from the open end of the large enclosing cylinder than those shock tubes which are close to the circumference and resulting in those shock tubes whose position is intermediate between the axis and the circumference of the large cylinder having an elevation between the elevation of the tubes on the axis and those near the circumference thereby producing a shallow conical cavity inside the large tube which produces the effect of a shaped charge in that the shock waves from the equilength shock tubes will reach the cavity at the same time producing a strong wave with force concentrated along the axis, as well as with some spherical component to impart energy both downward as well as outward for adequate hole diameter enlargement with all of the simultaneous ignition required being provided by parallel electric circuitry to the electric igniters and by small ignition ports opening into a sealed steep conical cavity at the upper end of the shock tubes, this cavity resulting from a sealed conical cover on the upper end of the outer cylinder said conical cover having the point of its cone upward and being provided with ignition and fueling ports. 